Book chapters will be unavailable on Saturday 24th August between 8am-12pm BST. This is for essential maintenance which will provide improved performance going forwards. Please accept our apologies for any inconvenience caused.
To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
A compact wideband out-of-phase power divider (PD) with improved isolation performance is proposed. This divider is formed by connecting an additional stub for isolation to output ports of a traditional Marchand balun with a defected ground structure (DGS) been used. To verify the design, a prototype divider is fabricated and tested. The measured results validate the 53.86% band-width centered at 3.43 GHz with more than 15 dB return loss at all ports, more than 17 dB isolation, respectively.
Liquid water on Mars might be created by deliquescence of hygroscopic salts or by permafrost melts, both potentially forming saturated brines. Freezing point depression allows these heavy brines to remain liquid in the near-surface environment for extended periods, perhaps as eutectic solutions, at the lowest temperatures and highest salt concentrations where ices and precipitates do not form. Perchlorate and chlorate salts and iron sulphate form brines with low eutectic temperatures and may persist under Mars near-surface conditions, but are chemically harsh at high concentrations and were expected to be incompatible with life, while brines of common sulphate salts on Mars may be more suitable for microbial growth. Microbial growth in saturated brines also may be relevant beyond Mars, to the oceans of Ceres, Enceladus, Europa and Pluto. We have previously shown strong growth of salinotolerant bacteria in media containing 2M MgSO4 heptahydrate (~50% w/v) at 25°C. Here we extend those observations to bacterial isolates from Basque Lake, BC and Hot Lake, WA, that grow well in saturated MgSO4 medium (67%) at 25°C and in 50% MgSO4 medium at 4°C (56% would be saturated). Psychrotolerant, salinotolerant microbes isolated from Basque Lake soils included Halomonas and Marinococcus, which were identified by 16S rRNA gene sequencing and characterized phenetically. Eutectic liquid medium constituted by 43% MgSO4 at −4°C supported copious growth of these psychrotolerant Halomonas isolates, among others. Bacterial isolates also grew well at the eutectic for K chlorate (3% at −3°C). Survival and growth in eutectic solutions increases the possibility that microbes contaminating spacecraft pose a contamination risk to Mars. The cold brines of sulphate and (per)chlorate salts that may form at times on Mars through deliquescence or permafrost melt have now been demonstrated to be suitable microbial habitats, should appropriate nutrients be available and dormant cells become vegetative.
Many novels, poems, and academic works produced in the last decades of Qing China were characterized by a structure of North–South dichotomy. While existing studies have investigated the root of this narrative structure in Chinese traditions, this article tries to uncover Japan's lesser-known role in the revitalization of traditional discourses. It first discusses how Japanese intellectuals, such as Shiga Shigetaka and Naitō Konan, reconfigured Chinese discourses on the North–South dichotomy as theories to assert Japan's superiority over China. It goes on to examine how Liang Qichao appropriated Japanese theories to mobilize southern Chinese to participate in state politics. It then explores how Chinese revolutionary students in Japan exploited Japanese intellectuals’ and Liang's discourses to promote a cross-provincial consciousness by representing China as a river-based region writ large. Lastly, it reveals how the restructured discourses on the North–South dichotomy were manipulated by revolutionaries after they flowed back to China.
True ileal digestibility (TID) values of amino acid (AA) obtained using growing rats are often used for the characterisation of protein quality in different foods and acquisition of digestible indispensable amino acid scores (DIAAS) in adult humans. Here, we conducted an experiment to determine the TID values of AA obtained from nine cooked cereal grains (brown rice, polished rice, buckwheat, oats, proso millet, foxtail millet, tartary buckwheat, adlay and whole wheat) fed to growing Sprague–Dawley male rats. All rats were fed a standard basal diet for 7 d and then received each diet for 7 d. Ileal contents were collected from the terminal 20 cm of ileum. Among the TID values obtained, whole wheat had the highest values (P<0·05), and polished rice, proso millet and tartary buckwheat had relatively low values. The TID indispensable AA concentrations in whole wheat were greater than those of brown rice or polished rice (P<0·05), and polished rice was the lowest total TID concentrations among the other cereal grains. The DIAAS was 68 for buckwheat, 47 for tartary buckwheat, 43 for oats, 42 for brown rice, 37 for polished rice, 20 for whole wheat, 13 for adlay, 10 for foxtail millet and 7 for proso millet. In this study, the TID values of the nine cooked cereal grains commonly consumed in China were used for the creation of a DIAAS database and thus gained public health outcomes.
This paper investigates a wideband and low axial ratio circularly polarized (CP) antenna, which is composed of a monopole on a novel polarization rotating reflective surface (PRRS) based on a corner-truncated artificial magnetic conductor (AMC) structure. By adjusting the dimensions of truncated corner properly, the PRRS has two polarization rotation (PR) frequency points. Then, a large PR band of 18% (5.55–6.65 GHz) can be achieved with two adjacent PR frequency points coming together. The profile of the newly PRRS is only0.04λ0. With corner-truncated AMC-based PRRS loading, a measured impedance bandwidth of 1.8 GHz (5.4–7.2 GHz) and the 3 dB axial ratio bandwidth of 1 GHz (5.55–6.65 GHz) could be obtained by the monopole antenna and validated by measurements. The values of AR were well below 1 dB at most of the CP region, which show a perfect CP performance. Moreover, the proposed antenna has exhibited a large axial ratio beamwidth in both the xoz- and yoz-planes and a peak gain of 6.1 dBic within the operational bandwidth.
The aims of this systematic review were to examine the effects of the overall and the different types of the interventions on the do-not-resuscitate (DNR) designation and the time between DNR and death among cancer patients.
Data were searched from the databases of PubMed, CINAHL, EMbase, Medline, and Cochrane Library through 2 November 2017. Studies were eligible for inclusion if they were (1) randomized control trails, quasi-experimental study, and retrospective observational studies and (2) used outcome indicators of DNR designation rates. The Effective Public Health Practice Project tool was used to assess the overall quality of the included studies.
The 14 studies with a total of 7,180 participants were included in this review. There were 78.6% (11 of 14) studies that indicated that the interventions could improve the DNR designation rates. Three types of DNR interventions were identified in this review: palliative care unit service, palliative consultation services, and patient-physician communication program. The significant increases of the time between DNR designation and death only occurred in a patient-physician communication program.
Significance of results:
The palliative care unit service provided a continuing care model to reduce unnecessary utilization of healthcare service. The palliative consultation service is a new care model to meet the needs of cancer patients in non-palliative care unit. The share decision-making communication program and physician's compassion attitudes facilitate to make DNR decision early. The individualized DNR program needs to be developed according to the needs of cancer patients.
In this paper, a single-band local surface plasmon mode resonance metamaterial filter is calculated and simulated. The damping constant of the gold film is optimized in simulations to eliminate the effects of the grain boundary and the surface scattering on the transmission property. The transmission property of the designed metamaterial filter can be enhanced through optimizing structural parameters (the vertical distance or radius of the gold particle). Two narrow transmission bands are achieved due to the electric field enhancement effect. The electric field enhancement factor η = |E|/|E0| is used to reveal the electric field resonance strength change. Higher transmission peak and larger field enhancement factor can be achieved than the pure gold hole array structure.
Congenital heart disease (CHD) is one of the most common birth defects. More than 200 susceptibility loci have been identified for CHDs, yet a large part of the genetic risk factors remain unexplained. Monozygotic (MZ) twins are thought to be completely genetically identical; however, discordant phenotypes have been found in MZ twins. Recent studies have demonstrated genetic differences between MZ twins. We aimed to test whether copy number variants (CNVs) and/or genetic mutation differences play a role in the etiology of CHDs by using single nucleotide polymorphism (SNP) genotyping arrays and whole exome sequencing of twin pairs discordant for CHDs. Our goal was to identify mutations present only in the affected twins, which could identify novel candidates for CHD susceptibility loci. We present a comprehensive analysis for the CNVs and genetic mutation results of the selected individuals but detected no consistent differences within the twin pairs. Our study confirms that chromosomal structure or genetic mutation differences do not seem to play a role in the MZ twins discordant for CHD.
The semilocal convergence of a third-order Newton-like method for solving nonlinear equations is considered. Under a weak condition (the so-called γ-condition) on the derivative of the nonlinear operator, we establish a new semilocal convergence theorem for the Newton-like method and also provide an error estimate. Some numerical examples show the applicability and efficiency of our result, in comparison to other semilocal convergence theorems.
Our aim was to examine the effect of supportive care interventions on depressive symptoms in patients with lung cancer.
We searched the databases of the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid EMBASE, PubMed, and the Chinese Electronic Periodical Services (CEPS) from their inception until September of 2015. We included randomized controlled trial studies that compared standard care with supportive care interventions. The standardized mean difference (SMD) (Cohen's d) was calculated to estimate the effect of interventions. Subgroup analysis was conducted to identify possible sources of heterogeneity.
A total of 1,472 patients with lung cancer were identified. Compared with standard care, the overall effects of all supportive care interventions significantly reduced depressive symptoms (SMD = –0.74, CI95% = –1.07 to –0.41), and the effects could be maintained at weeks 4, 8, and 12 of follow-up. Three types of supportive care interventions were identified: psychotherapy combined with psychoeducation, psychoeducation alone, and an exercise program. Both psychotherapy combined with psychoeducation and exercise significantly improved depressive symptoms, while psychoeducation alone did not yield significant effects. The moderating effects indicated that greater improvements in depressive symptoms were found in lung cancer patients with a severe level of depressive symptoms at baseline.
Significance of results:
Personalized supportive care interventions can be developed based on the main causes of depressive symptoms. Psychotherapy combined with psychoeducation can target the causes of depressive symptoms, including both physical distress and psychological trauma due to lung cancer, while exercise programs can effectively improve depressive symptoms for lung cancer patients with impaired respiratory function.
A novel hybrid processing has been developed to achieve dense and crack-free mullite films with large critical thicknesses. The amorphous solid nanoparticles obtained from the mullite sol–gel precursor were mixed with the same liquid precursor to form stable suspensions, which were subsequently used to form mullite coatings with the dip-coating method, followed by drying and firing. The hybrid precursor suspensions resulted in highly close-packed nanoparticles, which reduced shrinkage during sintering. Selecting the solvent with a low evaporation rate and high surface tension can effectively eliminate the surface instability caused by the lateral flow during solvent evaporation. The mullite film density was significantly improved at low sintering temperatures, because of the high packing density and viscous flow at above the glass transition temperature of the amorphous gel nanoparticles before crystallization. Dense and crack-free mullite films with 500–600 nm thickness can be obtained from the novel hybrid approach.
Nitrogen is an essential element for biological activity, and nitrogen isotopic compositions of geological samples record information about both marine biological processes and environmental evolution. However, only a few studies of N isotopes in the early Cambrian have been published. In this study, we analysed nitrogen isotopic compositions, as well as trace elements and sulphur isotopic compositions of cherts, black shales, carbonaceous shales and argillaceous carbonates from the Daotuo drill core in Songtao County, NE Guizhou Province, China, to reconstruct the marine redox environment of both deep and surface seawater in the study area of the Yangtze shelf margin in the early Cambrian. The Mo–U covariation pattern of the studied samples indicates that the Yangtze shelf margin area was weakly restricted and connected to the open ocean through shallow water flows. Mo and U concentrations, δ15Nbulk and δ34Spy values of the studied samples from the Yangtze shelf margin area suggest ferruginous but not sulphidic seawater and low marine sulphate concentration (relatively deep chemocline) in the Cambrian Fortunian and early Stage 2; sulphidic conditions (shallow chemocline and anoxic photic zone) in the upper Cambrian Stage 2 and lower Stage 3; and the depression of sulphidic seawater in the middle and upper Cambrian Stage 3. Furthermore, the decreasing δ15N values indicate shrinking of the marine nitrate reservoir during the middle and upper Stage 3, which reflects a falling oxygenation level in this period. The environmental evolution was probably controlled by the changing biological activity through its feedback on the local marine environment.
Classical molecular dynamics (MD), along with a bond-order potential for GaAs, has been used to study threshold displacement energies (Ed) of Ga and As recoils. Considering the crystallographic symmetry of GaAs, recoil events are confined in four unit stereographic triangles. To investigate the displacement energy’s dependence on crystallographic orientation, more than 3600 recoil events were simulated to uniformly sample values of Ed. Various defect configurations produced at these low energy recoils and the separation distances of Frenkel pairs were quantified and outlined. For both Ga and As, the minimum,
, is found to be 8 eV, but the maxima,
, are 22 and 28 eV for Ga and As, respectively. The distribution of Ed within unit stereographic triangles indicates that Ed shows a weak dependence on the recoil directions, in contrast to other semiconductors. The average threshold displacement energy is 13 ± 1 eV, which is in excellent agreement with available experiments.
An effective multiplex real-time polymerase chain reaction (PCR) assay for the simultaneous detection of three major pathogens, Nosema bombycis Nägeli (Microsporidia: Nosematidae), Bombyx mori nucleopolyhedrovirus (Baculoviridae: genus Alphabaculovirus) (NPV), and Bombyx mori densovirus (Parvoviridae: genus Iteravirus) (DNV), in silkworms (Bombyx mori (Linnaeus); Lepidoptera: Bombycidae) was developed in this study. Polymerase chain reaction and real-time PCR tests and basic local alignment search tool searches revealed that the primers and probes used in this study had high specificities for their target species. The ability of each primer/probe set to detect pure pathogen DNA was determined using a plasmid dilution panel, in which under optimal conditions the multiplex real-time PCR assay showed high efficiency in the detection of three mixed target plasmids with a detection limit of 8.5×103 copies for N. bombycis and Bombyx mori NPV (BmNPV) and 8.5×104 copies for Bombyx mori DNV (BmDNV). When the ability to detect these three pathogens was examined in artificially inoculated silkworms, our method presented a number of advantages over traditional microscopy, including specificity, sensitivity, and high-throughput capabilities. Under the optimal volume ratio for the three primer/probe sets (3:2:2=N. bombycis:BmNPV:BmDNV), the multiplex real-time PCR assay showed early detection of BmNPV and BmDNV by day 1 post inoculation using DNA templates of the three pathogens in various combinations from individually infected silkworms; the early detection of N. bombycis was possible by day 3 post inoculation using the DNA isolated from the midgut of N. bombycis-infected silkworms.
To track the course of development in children's fine-grained perception of Mandarin tones, the present study explored how categorical perception (CP) of Mandarin tones emerges along age among 70 four- to seven-year-old children and 16 adults. Prominent discrimination peaks were found for both the child and the adult groups, and they were well aligned with the corresponding identification crossovers. Moreover, six-year-olds showed a much narrower width (i.e. a sharper slope) compared to younger children, and have already acquired adult-like identification competence of Mandarin high-level and mid-rising tones. Although the ability to discriminate within-category tone pairs did not change, the between-category discrimination accuracies were positively correlated with chronological ages among child participants. We assume that the perceptual refinement of Mandarin tones in young children may be driven by an accumulation of perceptual development from the tonal information of the ambient sound input.
The Phoenix lander at Mars polar cap found appreciable levels of (per)chlorate salts, a mixture of perchlorate and chlorate salts of Ca, Fe, Mg and Na at levels of ~0.6% in regolith. These salts are highly hygroscopic and can form saturated brines through deliquescence, likely producing aqueous solutions with very low freezing points on Mars. To support planetary protection efforts, we have measured bacterial growth tolerance to (per)chlorate salts. Existing bacterial isolates from the Great Salt Plains of Oklahoma (NaCl-rich) and Hot Lake in Washington (MgSO4-rich) were tested in high concentrations of Mg, K and Na salts of chlorate and perchlorate. Strong growth was observed with nearly all of these salinotolerant isolates at 1% (~0.1 M) (per)chlorate salts, similar to concentrations observed in bulk soils on Mars. Growth in perchlorate salts was observed at concentrations of at least 10% (~1.0 M). Greater tolerance was observed for chlorate salts, where growth was observed to 2.75 M (>25%). Tolerance to K salts was greatest, followed by Mg salts and then Na salts. Tolerances varied among isolates, even among those within the same phylogenetic clade. Tolerant bacteria included genera that also are found in spacecraft assembly facilities. Substantial microbial tolerance to (per)chlorate salts is a concern for planetary protection since tolerant microbes contaminating spacecraft would have a greater chance for survival and proliferation, despite the harsh chemical conditions found near the surface of Mars.
In the present study, we evaluated the reproducibility and validity of dietary patterns among Chinese adult populations. A random subsample of 203 participants (aged 31–80 years) from a community-based nutrition and health survey was enrolled. An eighty-seven-item FFQ was administered twice (FFQ1 and FFQ2) 1 year apart; four 3 consecutive day, 24-h dietary recalls (24-HDR, as a reference method) were performed between the administrations of the two FFQ every 3 months. Dietary patterns from three separate dietary sources were derived using factor analysis based on twenty-eight predefined food groups. Comparisons between dietary pattern scores were made by using Pearson’s or intraclass correlation coefficients (ICC), cross-classification analysis, weighted κ statistic and Bland–Altman plots; the four major dietary patterns identified from FFQ1, FFQ2 and 24-HDR were similar. Regarding reproducibility, ICC for z-scores between FFQ1 and FFQ2 were all >0·6 for dietary patterns. The ‘animal and plant protein’ pattern had the highest ICC of 0·870. For validity, the adjusted Pearson’s correlation coefficients for dietary pattern z-scores between two FFQ and the mean of four 3 consecutive day 24-HDR ranged from 0·387 for the ‘Chinese traditional’ pattern to 0·838 for the ‘animal and plant protein’ pattern. More than 75 % of the participants were classified into the same or adjacent quartile, and <5 % were misclassified into opposite quartiles. The weighted κ ranged from 0·259 to 0·680. Bland–Altman plots indicated that no significant deviation was found between two dietary assessment methods. Our findings indicate a good reasonable reproducibility and a reasonable validity of dietary patterns derived by factor analysis in China.